Robot system that operates through a network firewall

ABSTRACT

A remote controlled robot system that includes a robot and a remote control station that communicate through a communication network. Communication with the robot is limited by a firewall coupled to the communication network. A communication server establishes communication between the robot and the remote control station so that the station can send commands to the robot through the firewall.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The subject matter disclosed generally relates to the field of mobiletwo-way teleconferencing.

2. Background Information

Robots have been used in a variety of applications ranging from remotecontrol of hazardous material to assisting in the performance ofsurgery. For example, U.S. Pat. No. 5,762,458 issued to Wang et al.discloses a system that allows a surgeon to perform minimally invasivemedical procedures through the use of robotically controlledinstruments. One of the robotic arms in the Wang system moves anendoscope that has a camera. The camera allows a surgeon to view asurgical area of a patient.

Tele-robots such as hazardous waste handlers and bomb detectors maycontain a camera that allows the operator to view the remote site.Canadian Pat. No. 2289697 issued to Treviranus, et al. discloses ateleconferencing platform that has both a camera and a monitor. Theplatform includes mechanisms to both pivot and raise the camera andmonitor. The Treviranus patent also discloses embodiments with a mobileplatform, and different mechanisms to move the camera and the monitor.

There has been marketed a mobile robot introduced by InTouchTechnologies, Inc., the assignee of this application, under thetrademark RP-7. The InTouch robot is controlled by a user at a remotestation. The remote station may be a personal computer with a joystickthat allows the user to remotely control the movement of the robot. Boththe robot and remote station have cameras, monitors, speakers andmicrophones to allow for two-way video/audio communication. The robotcamera provides video images to a screen at the remote station so thatthe user can view the robot's surroundings and move the robotaccordingly.

The InTouch robot system typically utilizes a broadband network such asthe Internet to establish a communication channel between the remotestation and the robot. The robot can be located at a facility which hasa firewall between the facility local network and the Internet. Thefirewall can inhibit remote access to the robot through the broadbandnetwork. It would be desirable to provide a system that would allowaccess to a remote robot that is protected by a local area networkfirewall.

BRIEF SUMMARY OF THE INVENTION

A remote controlled robot system that includes a robot and a remotecontrol station that communicate through a communication network. Therobot moves in response to robot control commands transmitted by theremote control station. The robot may be coupled to the communicationnetwork by a firewall. A communication server establishes communicationbetween the robot and the remote control station.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of a robotic system;

FIG. 2 is a schematic of an electrical system of a communication server;

FIG. 3 is a schematic of an electrical system of a robot;

FIG. 4 is a further schematic of the electrical system of the robot;

FIG. 5 is an illustration of a robot;

FIG. 6 is a graphical user interface of a remote station.

FIG. 7 is an illustration of a robot head.

DETAILED DESCRIPTION

Disclosed is a remote controlled robot system that includes a robot anda remote control station that communicate through a communicationnetwork. Communication with the robot is limited by a firewall coupledto the communication network. A communication server establishescommunication between the robot and the remote control station so thatthe station can send commands to the robot through the firewall.

Referring to the drawings more particularly by reference numbers, FIG. 1shows a robotic system 10 that can be used to conduct a remote visit.The robotic system 10 includes a robot 12, a base station 14 and aremote control station 16. The remote control station 16 may be coupledto the base station 14 through a network 18. By way of example, thenetwork 18 may be either a packet switched network such as the Internet,or a circuit switched network such has a Public Switched TelephoneNetwork (PSTN) or other broadband system. The base station 14 may becoupled to the network 18 by a modem (not shown) or other broadbandnetwork interface device. By way of example, the base station 14 may bea wireless router. Alternatively, the robot 12 may have a directconnection to the network thru for example a satellite.

The remote control station 16 may include a computer 22 that has amonitor 24, a camera 26, a microphone 28 and a speaker 30. The computer22 may also contain an input device 32 such as a joystick or a mouse.The control station 16 is typically located in a place that is remotefrom the robot 12. Although only one remote control station 16 is shown,the system 10 may include a plurality of remote stations. In general anynumber of robots 12 may be controlled by any number of remote stations16 or other robots 12. For example, one remote station 16 may be coupledto a plurality of robots 12, or one robot 12 may be coupled to aplurality of remote stations 16, or a plurality of robots 12.

Each robot 12 includes a movement platform 34 that is attached to arobot housing 36. Also attached to the robot housing 36 is a camera 38,a monitor 40, a microphone(s) 42 and a speaker(s) 44. The microphone 42and speaker 30 may create a stereophonic sound. The robot 12 may alsohave an antenna 46 that is wirelessly coupled to an antenna 48 of thebase station 14. The system 10 allows a user at the remote controlstation 16 to move the robot 12 through operation of the input device32. The robot camera 38 is coupled to the remote monitor 24 so that auser at the remote station 16 can view a subject such as a patient.Likewise, the robot monitor 40 is coupled to the remote camera 26 sothat the patient can view the user. The microphones 28 and 42, andspeakers 30 and 44, allow for audible communication between the patientand the user.

The remote station computer 22 may operate Microsoft OS software andWINDOWS XP or other operating systems such as LINUX. The remote computer22 may also operate a video driver, a camera driver, an audio driver anda joystick driver. The video images may be transmitted and received withcompression software such as MPEG CODEC.

The flow of information between the robot 12 and the control station 16may be limited by a firewall 50 on the robot side of the system and/or afirewall 51 on the control station side of the system. By way ofexample, the robot 12 and/or control station 16 may be located at afacility that contains one or more firewalls that control communicationbetween the facility local area network and the network 18. The system10 includes a communication server 52 that can establish communicationbetween the robot 12 and the remote control station 16.

The system may have the following hierarchy to establish communicationbetween the robot 12 and the remote control station 16. The remotecontrol station 16 may transmit an initial request to access a robot 12by transmitting one or more packets to an internal IP address of therobot 12. It being understood that each robot may have a unique IPaddress. If the robot 12 is not on the same network as the remotestation 16, this communication will fail.

If the initial attempt to access the robot is unsuccessful with theinternal IP address, the remote control station 16 may transmit arequest to the robot's external IP address. This may be done in eitherTCP or UDP protocol. If this attempt is unsuccessful, for example if thefirewall prevents access to the robot, the remote control station maysend a query to the communication server 52 which can then establishcommunication between the remote station 16 and the robot 12.

Many firewalls employ port address translation (“PAT”) to disguise anoutgoing message. For example, if a device such as the robot sends amessage with a source port number of 9000 the firewall 50/51 can changethe source port number to 47501. The firewall 50/51 will then only allowincoming messages to pass through if addressed to the translated port(e.g., 47501). Additionally, the firewall 50/51 may also only allowincoming messages if the message packet came from a source port recentlycommunicated to by the robot, and the destination port of the packetmatches the source port of a packet recently received from the source.

Each robot 12 may establish a constant link with a communication port ofthe server 52. Alternatively, each robot may periodically poll theserver 52. With either method the server knows the last known IP addressof robots and control stations, as well as the peer to peer UDP portsopen on each. Upon receiving a query from a remote control station 16,the server 52 can forward both IP and port information on both the robot12 and the remote station, so that both the remote station 16 and robot12 can simultaneously send to peer to peer packets to each other,bypassing problems caused by PAT tables. The last known IP address maybe the PAT address provided by the firewall 50. Upon receiving a queryfrom a remote control station 16, the server 52 can forward the PATaddress to the remote station 16, so that the station 16 can establish apeer to peer communication with the robot 12.

Alternatively, or in the event a peer to peer communication cannot beestablished, the server 52 can provide a conduit for communicationbetween the remote control station 16 and the robot 12. For example,packets directed to the communication server 52, which then retransmitsthe packets to the robot 12 using the last known IP address. In thismode, the server 52 can establish UDP connectivity with both the remotecontrol station 16 and the robot 12. The server 52 instructs the robot12 and the remote station 16 to open a UDP socket and transmit UDPpackets to a specified server port.

The server 52 provides a conduit to allow communication between aplurality of control stations and a single robot, a single controlstation and a plurality of robots, or a plurality of control stationswith a plurality of robots.

FIG. 2 shows an embodiment of a communication server 52. The server mayinclude one or more processors 60 connected to one or more memorydevices 62. The memory device 62 may include both volatile andnon-volatile memory such as read only memory (ROM) or random accessmemory (RAM). The processor 60 is capable of operating software programsin accordance with instructions and data stored within the memory device62.

The processor 60 may be coupled to a communication port 64, a massstorage device 66, a monitor 68 and a keyboard 70 through a system bus72. The communication port 64 may include an ETHERNET interface thatallows data to be transmitted and received in TCP/IP or UDP format. Thesystem bus 72 may be PCI or another conventional computer bus. The massstorage device 66 may include one or more disk drives such as magneticor optical drives.

Without limiting the scope of the invention the term computer readablemedium may include the memory device 62 and/or the mass storage device66. The computer readable medium will contain software programs inbinary form that can be read and interpreted by the computer. Inaddition to the memory device 62 and/or mass storage device 66, computerreadable medium may also include a diskette, a compact disc, anintegrated circuit, a cartridge, or even a remote communication of thesoftware program.

The server 52 may contain a number of graphical user interfaces thatallow a user to control communication between the remote station and therobot. The server 52 can control robot access for a designated timeperiod. For example, the server can limit the time a particular remotestation can control a robot to two hours of access time. The serverallows a system operator to charge a robot access fee or other form ofcompensation that is divisible by units of time.

In alternative embodiments, the server 52 may also be a networkappliance rather than a full computer with an operating system.Alternatively, the server 52 may in fact be a distributed network ofphysical servers or network devices, each at different IP addresses, forwhich a given robot 12 and remote station 16 may be connected todifferent physical devices, and those physical devices share data aboutthe systems connected to the devices. In cases where a server 52 is usedas a data conduit, one of the following may occur: (a) either the robot12 or remote station 16 is instructed to disconnect from one physicaldevice and re-connect to the same physical device to which the otherdevice is connected, or (b) the data within the server network istransmitted from one server to another as necessary. In addition, theserver 52 may have a router, firewall or similar device, with sufficientport forwarding and/or packet management to effect the same behavior asif residing on the public Internet, for purposes of communication withthe robots 12 and remote stations 16.

FIGS. 3 and 4 show an embodiment of a robot 12. Each robot 12 mayinclude a high level control system 150 and a low level control system152. The high level control system 150 may include a processor 154 thatis connected to a bus 156. The bus 156 is coupled to the camera 38 by aninput/output (I/O) port 158. The monitor 40 is coupled to the bus 156 bya serial output port 160 and a VGA driver 162. The monitor 40 mayinclude a touchscreen function that allows the patient to enter input bytouching the monitor screen.

The speaker 44 is coupled to the bus 156 by a digital to analogconverter 164. The microphone 42 is coupled to the bus 156 by an analogto digital converter 166. The high level controller 150 may also containrandom access memory (RAM) device 168, a non-volatile RAM device 170 anda mass storage device 172 that are all coupled to the bus 156. The massstorage device 172 may contain medical files of the patient that can beaccessed by the user at the remote control station 16. For example, themass storage device 172 may contain a picture of the patient. The user,particularly a health care provider, can recall the old picture and makea side by side comparison on the monitor 24 with a present video imageof the patient provided by the camera 38. The robot antennae 46 may becoupled to a wireless transceiver 174. By way of example, thetransceiver 174 may transmit and receive information in accordance withIEEE 802.11b.

The controller 154 may operate with a LINUX OS operating system. Thecontroller 154 may also operate MS WINDOWS along with video, camera andaudio drivers for communication with the remote control station 16.Video information may be transceived using MPEG CODEC compressiontechniques. The software may allow the user to send e-mail to thepatient and vice versa, or allow the patient to access the Internet. Ingeneral the high level controller 150 operates to control communicationbetween the robot 12 and the remote control station 16.

The remote control station 16 may include a computer that is similar tothe high level controller 150. The computer would have a processor,memory, I/O, software, firmware, etc. for generating, transmitting,receiving and processing information.

The high level controller 150 may be linked to the low level controller152 by serial ports 176 and 178. The low level controller 152 includes aprocessor 180 that is coupled to a RAM device 182 and non-volatile RAMdevice 184 by a bus 186. Each robot 12 contains a plurality of motors188 and motor encoders 190. The motors 188 can actuate the movementplatform and move other parts of the robot such as the monitor andcamera. The encoders 190 provide feedback information regarding theoutput of the motors 188. The motors 188 can be coupled to the bus 186by a digital to analog converter 192 and a driver amplifier 194. Theencoders 190 can be coupled to the bus 186 by a decoder 196. Each robot12 also has a number of proximity sensors 198 (see also FIG. 1). Thesensors 198 can be coupled to the bus 186 by a signal conditioningcircuit 200 and an analog to digital converter 202.

The low level controller 152 runs software routines that mechanicallyactuate the robot 12. For example, the low level controller 152 providesinstructions to actuate the movement platform to move the robot 12. Thelow level controller 152 may receive movement instructions from the highlevel controller 150. The movement instructions may be received asmovement commands from the remote control station or another robot.Although two controllers are shown, it is to be understood that eachrobot 12 may have one controller, or more than two controllers,controlling the high and low level functions.

The various electrical devices of each robot 12 may be powered by abattery(ies) 204. The battery 204 may be recharged by a batteryrecharger station 206 (see also FIG. 1). The low level controller 152may include a battery control circuit 208 that senses the power level ofthe battery 204. The low level controller 152 can sense when the powerfalls below a threshold and then send a message to the high levelcontroller 150.

FIG. 5 shows an embodiment of the robot 12. The robot 12 may include aholonomic platform 250 that is attached to a robot housing 252. Theholonomic platform 250 provides three degrees of freedom to allow therobot 12 to move in any direction.

The robot 12 may have a pedestal assembly 254 that supports the camera38 and the monitor 40. The pedestal assembly 254 may have two degrees offreedom so that the camera 38 and monitor 40 can together be swiveledand pivoted as indicated by the arrows.

The camera 38 and monitor 40 may in accordance with a closed loopcontrol system. The platform 250 is located within a platform referencecoordinate system that may have axes X_(p), Y_(p) and Z_(p). By way ofexample, the y-axis Y_(p) may extend from a nose of the platform 250.The camera 38 is fixed to a camera reference coordinate system that mayhave axes X_(c), Y_(c) and Z_(c). The y-axis Y_(c) may extendperpendicular from the camera lens. When the robot is initialized, they-axis Y_(c) of the camera coordinate system may be aligned with they-axis Y_(p) of the platform coordinate system. A forward pivoting ofthe joystick 32 (shown in FIG. 1) may cause a corresponding movement ofthe platform 250 in the direction of the y-axis Y_(p) in the platformcoordinate system.

The robot may have a drive vector that may have axes X_(d), Y_(d), andZ_(d) that is mapped to the camera coordinate system, the platformcoordinate system or some other system. By way of example, the y-axisY_(p) may extend in the direction of forward motion. Mapping includesthe process of transforming an input command into a directional movementrelative to one or more coordinate systems. The robot controller mayperform certain algorithms to translate input commands to platformmovement in accordance with a specified mapping scheme. For example,when the drive vector is mapped to the camera coordinate system thecontroller computes the drive vector of the input command relative tothe camera coordinate system. In a platform mapping scheme the inputdrive vector is computed relative to the platform coordinate system. Inyet another scheme the drive vector can be computed relative to anothercoordinate system, such as a world coordinate system (eg. coordinatesystem relative to the ground) that is independent of the camera orplatform coordinate systems. Mapping the drive vector to the cameracoordinate system may be desirable because all movement would berelative to the image viewed by the user, providing a system that isintuitive to use.

A twisting of the joystick 32 may cause the camera 38 to swivel asindicated by arrows 4. For example, if the joystick 32 is twisted +45degrees the camera 38 will pivot +45 degrees. Swiveling the camera 38also moves the y-axis Y_(c) of the camera coordinate system, because they-axis Y_(c) is fixed to the camera. This may be different than thedrive direction. The remote station computer may operate a program togenerate a command that will automatically rotate the platform 250 torealign the y-axis Y_(p) of the platform coordinate system with they-axis Y_(c) of the camera coordinate system. For the above example, theplatform 250 is rotated +45 degrees. This approach keeps the platform250 aligned with the camera 38, so that any subsequent movement of therobot will be intuitive relative to the image provided by the camera.For example, a forward pivot of the joystick will induce a forwardmovement of the robot as viewed through the monitor of the remotestation. In this driving scheme, the platform may not be aligned withthe head. The computer may generate trajectory planning for the platformcoordinate system to move into alignment with the head coordinate systemover a period of time or distance traveled, with or without an initialdelay in time or some distance.

The system may be configured so that pivotal movement of the joystick 32may be mapped to a corresponding directional movement of the robot. Forexample, pivoting the joystick along a +45 degree may cause the robot tomove in a +45 degree direction relative to the y-axis. Y_(c) of thecamera coordinate frame. Alternatively, the camera may pan +45 degreesand the platform 250 may rotate +45 degrees before forward movement bythe robot. The automatic panning and platform rotation causes the robotto move in a forward direction as depicted by the image provided by thecamera. The robot may have a mode wherein the user can twist thejoystick to pan the camera during robot movement such that the movementis not in the direction the camera is pointing. This allows the user tovisually pan while moving the robot. The joystick may have a springreturn that automatically returns the position of the stick whenreleased by the user. This causes the camera to be aligned with thedirection of movement.

In general the robot may have a number of different mapping schemes andrelative, dependent or independent, movement between the camera, theplatform and drive direction. Relative movement between the camera andplatform may occur in a camera based mapping scheme, a platform basedmapping scheme, or some other scheme.

Although, the automatic platform rotation commands have been describedas be generated by the remote station computer, it is to be understoodthat the robot may determine the commands and signals necessary tore-orient the platform 250 and/or the camera 38. The robot 12 mayinclude a potentiometer (not shown) that tracks the position of thecamera and provides feedback to the low level controller 152. The lowlevel controller 152 may automatically rotate the platform to align they-axes Y_(c) and Y_(p) or otherwise compensate for camera movement. Amode button (not shown) may allow the operator to place the system ineither a tracking mode or a normal mode. In the tracking mode the robotmoves relative to the camera coordinate system so that movement isintuitive relative to the screen even when the camera is panned. Innormal mode the robot moves within the platform coordinate system.

The system may be the same or similar to a robotic system provided bythe assignee InTouch-Health, Inc. of Santa Barbara, Calif. under thename RP-7. The system may also be the same or similar to the systemdisclosed in U.S. Pat. No. 6,925,357 issued Aug. 2, 2005, which ishereby incorporated by reference.

FIG. 6 shows a display user interface (“DUI”) 300 that can be displayedat the remote station 16. The DUI 300 may include a robot view field 302that displays a video image provided by the camera of the robot. The DUI300 may also include a station view field 304 that displays a videoimage provided by the camera of the remote station 16. The DUI 300 maybe part of an application program stored and operated by the computer 22of the remote station 16. The display user interface and the variousfeatures and functions provided by the interface may be the same orsimilar as the DUI provided by the RP-7 system.

In operation, the robot 12 may be placed in a home or a facility whereone or more patients are to be monitored and/or assisted. The facilitymay be a hospital or a residential care facility. By way of example, therobot 12 may be placed in a home where a health care provider maymonitor and/or assist the patient. Likewise, a friend or family membermay communicate with the patient. The cameras and monitors at both therobot and remote control stations allow for teleconferencing between thepatient and the person at the remote station(s).

The robot 12 can be maneuvered through the home or a facility bymanipulating the input device 32 at a remote station 16. The robot 10may be controlled by a number of different users. To accommodate forthis the robot may have an arbitration system. The arbitration systemmay be integrated into the operating system of the robot 12. Forexample, the arbitration technique may be embedded into the operatingsystem of the high-level controller 150.

By way of example, the users may be divided into classes that includethe robot itself, a local user, a caregiver, a doctor, a family member,or a service provider. The robot 12 may override input commands thatconflict with robot operation. For example, if the robot runs into awall, the system may ignore all additional commands to continue in thedirection of the wall. A local user is a person who is physicallypresent with the robot. The robot could have an input device that allowslocal operation. For example, the robot may incorporate a voicerecognition system that receives and interprets audible commands.

A caregiver is someone who remotely monitors the patient. A doctor is amedical professional who can remotely control the robot and also accessmedical files contained in the robot memory. The family and serviceusers remotely access the robot. The service user may service the systemsuch as by upgrading software, or setting operational parameters.

The robot 12 may operate in one of two different modes; an exclusivemode, or a sharing mode. In the exclusive mode only one user has accesscontrol of the robot. The exclusive mode may have a priority assigned toeach type of user. By way of example, the priority may be in order oflocal, doctor, caregiver, family and then service user. In the sharingmode two or more users may share access with the robot. For example, acaregiver may have access to the robot, the caregiver may then enter thesharing mode to allow a doctor to also access the robot. Both thecaregiver and the doctor can conduct a simultaneous tele-conference withthe patient.

The system 10 can be used for doctor proctoring where a doctor at theremote station provides instructions and feedback to a doctor located inthe vicinity of the robot. For example, a doctor at the remote locationcan view a patient and assist a doctor at the patient location in adiagnosis. Likewise, the remote doctor can assist in the performance ofa medical procedure at the robot location.

The arbitration scheme may have one of four mechanisms; notification,timeouts, queue and call back. The notification mechanism may informeither a present user or a requesting user that another user has, orwants, access to the robot. The timeout mechanism gives certain types ofusers a prescribed amount of time to finish access to the robot. Thequeue mechanism is an orderly waiting list for access to the robot. Thecall back mechanism informs a user that the robot can be accessed. Byway of example, a family user may receive an e-mail message that therobot is free for usage. Tables I and II, show how the mechanismsresolve access request from the various users.

TABLE I Access Medical Command Software/Debug Set User Control RecordOverride Access Priority Robot No No Yes (1) No No Local No No Yes (2)No No Caregiver Yes Yes Yes (3) No No Doctor No Yes No No No Family NoNo No No No Service Yes No Yes Yes Yes

TABLE II Requesting User Local Caregiver Doctor Family Service CurrentLocal Not Allowed Warn current user of Warn current user of Warn currentuser of Warn current user of User pending user pending user pending userpending user Notify requesting Notify requesting user Notify requestinguser Notify requesting user that system is in that system is in use thatsystem is in use user that system is in use Set timeout = 5 m Settimeout = 5 m use Set timeout Call back No timeout Call back CaregiverWarn current user Not Allowed Warn current user of Warn current user ofWarn current user of of pending user. pending user pending user pendinguser Notify requesting Notify requesting user Notify requesting userNotify requesting user that system is that system is in use that systemis in use user that system is in in use. Set timeout = 5 m Set timeout =5 m use Release control Queue or callback No timeout Callback DoctorWarn current user Warn current user of Warn current user of Notifyrequesting user Warn current user of of pending user pending userpending user that system is in use pending user Notify requesting Notifyrequesting Notify requesting user No timeout Notify requesting user thatsystem is user that system is in that system is in use Queue or callbackuser that system is in in use use No timeout use Release control Settimeout = 5 m Callback No timeout Callback Family Warn current userNotify requesting Warn current user of Warn current user of Warn currentuser of of pending user user that system is in pending user pending userpending user Notify requesting use Notify requesting user Notifyrequesting user Notify requesting user that system is No timeout thatsystem is in use that system is in use user that system is in in use Putin queue or Set timeout = 1 m Set timeout = 5 m use Release Controlcallback Queue or callback No timeout Callback Service Warn current userNotify requesting Warn current user of Warn current user of Not Allowedof pending user user that system is in request pending user Notifyrequesting use Notify requesting user Notify requesting user user thatsystem is No timeout that system is in use that system is in use in useCallback No timeout No timeout No timeout Callback Queue or callback

The information transmitted between the station 16 and the robot 12 maybe encrypted. Additionally, the user may have to enter a password toenter the system 10. A selected robot is then given an electronic key bythe station 16. The robot 12 validates the key and returns another keyto the station 16. The keys are used to encrypt information transmittedin the session.

The robot 12 and remote station 16 transmit commands through thebroadband network 18. The commands can be generated by the user in avariety of ways. For example, commands to move the robot may begenerated by moving the joystick 32 (see FIG. 1). Table III provides alist of control commands that are generated at the remote station andtransmitted to the robot through the network.

TABLE III Control Commands Command Example Description drive drive 10.00.0 5.0 The drive command directs the robot to move at the specifiedvelocity (in cm/sec) in the (x, y) plane, and turn its facing at thespecified rate (degrees/sec). goodbye goodbye The goodbye commandterminates a user session and relinquishes control of the robotgotoHomePosition gotoHomePosition 1 The gotoHomePosition command movesthe head to a fixed “home” position (pan and tilt), and restores zoom todefault value. The index value can be 0, 1, or 2. The exact pan/tiltvalues for each index are specified in robot configuration files. headhead vel pan 5.0 tilt The head command controls the head motion. 10.0 Itcan send commands in two modes, identified by keyword: either positional(“pos”) or velocity (“vol”). In velocity mode, the pan and tilt valuesare desired velocities of the head on the pan and tilt axes, indegree/sec. A single command can include just the pan section, or justthe tilt section, or both. keepalive keepalive The keepalive commandcauses no action, but keeps the communication (socket) link open so thata session can continue. In scripts, it can be used to introduce delaytime into the action. odometry odometry 5 The odometry command enablesthe flow of odometry messages from the robot. The argument is the numberof times odometry is to be reported each second. A value of 0 turnsodometry off. reboot reboot The reboot command causes the robot computerto reboot immediately. The ongoing session is immediately broken off.restoreHeadPosition restoreHeadPosition The restoreHeadpositionfunctions like the gotoHomePosition command, but it homes the head to aposition previously saved with gotoHomePosition. saveHeadPositionsaveHeadPosition The saveHeadPosition command causes the robot to savethe current head position (pan and tilt) in a scratch location intemporary storage so that this position can be restored. Subsequentcalls to “restoreHeadPosition” will restore this saved position. Eachcall to saveHeadPosition overwrites any previously saved position.setCameraFocus setCameraFocus 100.0 The setCameraFocus command controlsfocus for the camera on the robot side. The value sent is passed “raw”to the video application running on the robot, which interprets itaccording to its own specification. setCameraZoom setCameraZoom 100.0The setCameraZoom command controls zoom for the camera on the robotside. The value sent is passed “raw” to the video application running onthe robot, which interprets it according to its own specification.shutdown Shutdown The shutdown command shuts down the robot and powersdown its computer. stop stop The stop command directs the robot to stopmoving immediately. It is assumed this will be as sudden a stop as themechanism can safely accommodate. timing Timing 3245629 500 The timingmessage is used to estimate message latency. It holds the UCT value(seconds + milliseconds) of the time the message was sent, as recordedon the sending machine. To do a valid test, you must compare results ineach direction (i.e., sending from machine A to machine B, then frommachine B to machine A) in order to account for differences in theclocks between the two machines. The robot records data internally toestimate average and maximum latency over the course of a session, whichit prints to log files. userTask userTask “Jane Doe” The userTaskcommand notifies the robot of “Remote Visit” the current user and task.It typically is sent once at the start of the session, although it canbe sent during a session if the user and/or task change. The robot usesthis information for record-keeping.

Table IV provides a list of reporting commands that are generated by therobot and transmitted to the remote station through the network.

TABLE IV Reporting Commands Command Example Description abnormalExitabnormalExit This message informs the user that the robot software hascrashed or otherwise exited abnormally. Te robot software catches top-level exceptions and generates this message if any such exceptionsoccur. bodyType bodyType 3 The bodyType message informs the stationwhich type body (using the numbering of the mechanical team) the currentrobot has. This allows the robot to be drawn correctly in the stationuser interface, and allows for any other necessary body-specificadjustments. driveEnabled driveEnabled true This message is sent at thestart of a session to indicate whether the drive system is operational.emergencyShutdown emergencyShutdown This message informs the stationthat the robot software has detected a possible “runaway” condition (anfailure causing the robot to move out of control) and is shutting theentire system down to prevent hazardous motion. odometry odometry 10 20340 The odometry command reports the current (x, y) position (cm) andbody orientation (degrees) of the robot, in the original coordinatespace of the robot at the start of the session. sensorGroup group_dataSensors on the robot are arranged into groups, each group of a singletype (bumps, range sensors, charge meter, etc.) The sensorGroup messageis sent once per group at the start of each session. It contains thenumber, type, locations, and any other relevant data for the sensors inthat group. The station assumes nothing about the equipment carried onthe robot; everything it knows about the sensors comes from thesensorGroup messages. sensorState groupName state data The sensorStatecommand reports the current state values for a specified group ofsensor. The syntax and interpretation for the state data is specific toeach group. This message is sent once for each group at each sensorevaluation (normally several times per second). systemError systemErrorThis message informs the station user of a driveController failure inone of the robot's subsystems. The error_type argument indicates whichsubsystem failed, including driveController, sensorController, headHome.systemInfo systemInfo wireless 45 This message allows regular reportingof information that falls outside the sensor system such as wirelesssignal strength. text text “This is some The text string sends a textstring from the text” robot to the station, where the string isdisplayed to the user. This message is used mainly for debugging.version version 1.6 This message identifies the software versioncurrently running on the robot. It is sent once at the start of thesession to allow the station to do any necessary backward compatibilityadjustments.

The processor 154 of the robot high level controller 150 may operate aprogram that determines whether the robot 12 has received a robotcontrol command within a time interval. For example, if the robot 12does not receive a control command within 2 seconds then the processor154 provides instructions to the low level controller 150 to stop therobot 12. Although a software embodiment is described, it is to beunderstood that the control command monitoring feature could beimplemented with hardware, or a combination of hardware and software.The hardware may include a timer that is reset each time a controlcommand is received and generates, or terminates, a command or signal,to stop the robot.

The remote station computer 22 may monitor the receipt of video imagesprovided by the robot camera. The computer 22 may generate and transmita STOP command to the robot if the remote station does not receive ortransmit an updated video image within a time interval. The STOP commandcauses the robot to stop. By way of example, the computer 22 maygenerate a STOP command if the remote control station does not receive anew video image within 2 seconds. Although a software embodiment isdescribed, it is to be understood that the video image monitoringfeature could be implemented with hardware, or a combination of hardwareand software. The hardware may include a timer that is reset each time anew video image is received and generates, or terminates, a command orsignal, to generate the robot STOP command.

The robot may also have internal safety failure features. For example,the robot may monitor communication between the robot controller and therobot servo used to operate the platform motors. The robot monitor mayswitch a relay to terminate power to the platform motors if the monitordetects a lack of communication between the robot controller and themotor servo.

The remote station may also have a safety feature for the input device32. For example, if there is no input from the joystick for a certaintime interval (eg. 10 seconds) the computer 22 may not relay subsequentinput unless the user presses a button for another time interval (eg. 2seconds), which reactivates the input device.

FIG. 7 shows another embodiment of the robot as a robot head 350 thatcan both pivot and spin the camera 38 and the monitor 40. The robot head350 can be similar to the robot 12 but without the platform 250. Therobot head 350 may have actuators 352 and linkages 354 to pivot thecamera 38 and monitor 40 about a pivot axis 4, and spin the camera 38and monitor 40 about a spin axis 5. The pivot axis may intersect thespin axis. Having a robot head 350 that both pivots and spins provides awide viewing area. The robot head 350 may be in the system either withor instead of the mobile robot 12. The robot head can be particularlyuseful for doctor proctoring. The head can be located at a medicalfacility such as an emergency room or a doctor's office. A doctor at theremote location can assist in the diagnosis and medical treatment of apatient located at the robot location. The doctor can move the head toview the patient through control commands from the remote controlstation. Doctor proctoring can also be performed with a mobile robot 12.

While certain exemplary embodiments have been described and shown in theaccompanying drawings, it is to be understood that such embodiments aremerely illustrative of and not restrictive on the broad invention, andthat this invention not be limited to the specific constructions andarrangements shown and described, since various other modifications mayoccur to those ordinarily skilled in the art.

What is claimed is:
 1. A remote controlled robot system that is coupled to a communication network, comprising: a remote control station that transmits a robot control command; a robot that includes a monitor and a camera, and moves in response to said robot control command; a communication server that establishes a communication between said remote control station and said robot for a designated time period that defines an entire allowable time interval in which said remote control station can control said robot.
 2. The system of claim 1, wherein said communication server instructs said remote control station and said robot to transmit information to at least one designated port of said communication server.
 3. The system of claim 1, further comprising one or more additional communication servers and information is transmitted between said servers.
 4. The system of claim 1, further comprising one or more additional communication servers, and either said robot or said remote control station is instructed to disconnect from one server and reconnect to a server connected to said remote control station or said robot.
 5. The system of claim 1, wherein said robot control command is sent to said communication server from said remote control station, and then retransmitted from said communication server to said robot.
 6. The system of claim 1, wherein said communication server allows a server operator to charge a fee that is divisible by units of time.
 7. The system of claim 1, wherein said robot moves in accordance with a closed loop control scheme.
 8. A method for remotely controlling a robot that has a camera and a monitor, and being coupled to a communication network by a firewall, comprising: establishing, by a communication server, a communication between the robot and a remote control station through the firewall for a designated time period that defines an entire allowable time interval in which the remote controls station can control the robot; transmitting robot control commands from the remote control station to the robot; moving the robot in accordance with the robot control command; and, terminating control of the robot by the remote control station at the end of the time interval.
 9. The method of claim 8, wherein the robot periodically polls a communication server that establishes the communication between the robot and the remote control station.
 10. The method of claim 8, wherein the communication between the remote control station and the robot is limited to a designated time period.
 11. The method of claim 8, wherein the robot control command is sent to a communication server from the remote control station, and then retransmitted from the communication server to the robot.
 12. A remote controlled robot system that is coupled to a communication network, comprising: a firewall that connects a local area network to an external network; a robot coupled to said local area network, said robot includes a monitor and a camera; and, a remote control station that transmits a robot control command to a first robot IP address on said local area network and retransmits said robot control command to a second robot IP address on said external network if said transmission to said first robot IP address failed, and wherein said robot moves in response to said robot control command.
 13. The system of claim 12, wherein said remote control station and said robot communicate with UDP packets.
 14. The system of claim 12, wherein said robot control command is sent to a communication server from said remote control station, and then retransmitted from said communication server to said robot.
 15. The system of claim 12, wherein said robot includes said camera and said monitor that move together in at least two degrees of freedom.
 16. The system of claim 12, wherein said robot moves in accordance with a closed loop control scheme.
 17. The communication server of claim 12, wherein said communication server establishes a communication between the remote control station and the robot for a designated time period that defines an entire time interval in which said remote control station controls said robot.
 18. A remote controlled robot system that is coupled to a communication network, comprising: a remote control station that transmits a robot control command and is coupled to the communication network by a control station firewall; a robot that is coupled to the communication network by a robot firewall; a communication server that establishes a communication between said remote control station and said robot through the remote control station and robot firewalls by instructing said remote control station and said robot to essentially simultaneously send peer to peer packets to each other.
 19. The system of claim 18, wherein said communication server instructs said remote control station and said robot to transmit information to each other.
 20. The system of claim 18, wherein said robot periodically polls said communication server.
 21. The system of claim 18, wherein said communication server allows communication between said remote control station and said robot for a designated time period that defines an entire time interval in which said remote control station controls said robot.
 22. The system of claim 18, further comprising a plurality of remote control stations and a plurality of mobile robots and said communication server links said remote stations with said mobile robots. 